* Ismail Haniyeh - Haniyeh, 50, held the No. 1 spot on Hamas' national list of parliamentary candidates. A resident of the Shati refugee camp in the Gaza Strip, Haniyeh also heads Hamas' student movement at the Islamic University in Gaza. He had served as bureau chief for Sheikh Ahmed Yassin, Hamas' founder. Haniyeh is seen as the leading pragmatist among the Hamas leadership in the territories, and served for long periods as the liaison between the movement and entities in the West. · * Dr. Mahmoud Zahar - A surgeon by profession, Zahar, 55, is a lecturer in medicine at the Islamic University in Gaza. For most of the 1990s, he served as Hamas' chief spokesman in the Gaza Strip. Zahar was among the group of Hamas members who were deported to Lebanon in 1992. He held the No. 9 spot on Hamas' national list for the elections. He has been the target of two Israeli assassination attempts, with the second strike resulting in the death of his eldest son when his home was bombed. Until recently, he was considered Hamas most senior official in the Strip.

* Mohammed Abu Tir - No. 2 on Hamas' national list of parliamentary candidates, Abu Tir, 55, is a resident of the village of Umm Tuba in southeast Jerusalem. Originally a Fatah activist, Abu Tir joined Hamas upon its establishment. He was released from an Israeli jail six months ago after having served 22 years for possessing arms and providing assistance to Hamas cells in the West Bank. · * Hassan Yousef - Yousef, 50, is a resident of the town of Bituniya, near Ramallah, and headed Hamas' list in the region. Yousef was among the Hamas members deported to Lebanon in 1992. In Israeli custody for the past two months due to his activities with the movement, Yousef played a major role in Hamas' entry into politics. He is believed to have close ties with Fatah leaders, for which he has been criticized by Hamas. · * Na'af Rajoub - Rajoub, 47, is the brother of Jibril Rajoub, former head of the Palestinian preventative security mechanism. Rajoub is a resident of Dura in the southern Hebron Hills, and headed the movement's list in the region. He was among the Hamas deportees of 1992.

Democrats will rightly applaud the 78% turnout in Wednesday's elections to the Palestinian parliament, which were remarkably fair, free and peaceful. George Bush and Tony Blair, who set such store by promoting democracy in Iraq and (selectively) elsewhere in the Middle East, should be delighted. The only problem is the result: preliminary figures show a stunning victory for the Islamic Resistance Movement, Hamas, long shunned as a terrorist organisation not only by Israel but also by the US, Europe and Russia. This is a catastrophic defeat for Fatah, the natural party of liberation and government for Palestinians for 40 years and for half that period committed to a two-state solution to this most intractable of conflicts.

Hamas is no ordinary political party. Until it participated in this election it was best known in Israel and abroad for the suicide attacks it used against its Israeli enemies. In Gaza and the West Bank it was admired for its network of social services and opposition to the corruption which became a byword for Fatah and the PLO, under Yasser Arafat and then Mahmoud Abbas. Ideologically, Hamas is close to where the PLO was 30 years ago, wedded to armed struggle and to the replacement of Israel by a Palestinian state. It was hardly a good sign when its leader in exile met recently with the Iranian president, who calls for the eradication of Israel. Rhetoric and reality may, however, be different: Hamas's election manifesto did not repeat the call of its charter for the destruction of the Jewish state. It has been disciplined enough to largely observe a year-long ceasefire and has hinted it may continue that indefinitely. Its electoral triumph probably owes less to its resistance to occupation - an unequal struggle against Israeli F16's, Hellfire missiles and targeted assassinations - than to its demand for clean hands and delivery.

Paradoxically, a victory whose scale was unanticipated even by expert local pollsters, might - just - turn out to be better news that it looks. Had Hamas won just a few ministerial seats in a powersharing cabinet dominated by Fatah, the tension between politics and resistance could have been hard to resolve. If its parliamentary majority - 76 out of 132 seats, to Fatah's 43 - is to mean total responsibility, the Kalashnikovs and explosive belts will have to go. It is hard to imagine Hamas running an effective government without dealing with Israelis. It is even harder to see the Israelis dealing with it except through the barrel of a gun if bombs start going off on buses in Tel Aviv.

That is why the right response to this result is to insist that Hamas make clear that it is committed to negotiations with Israel. The new parliament should pass and implement a draft political parties law requiring armed militias to disband. By the same token Israel must meet its obligations under the internationally backed "road map" for peace, including the cessation of all settlement activity. Israel will be deeply sceptical both of Hamas's intentions and outside advice and will be tempted to go for more unilateral moves on the model of the Gaza pullout pushed through by Ariel Sharon last summer. It will be hard to argue with Ehud Olmert, Mr Sharon's successor, facing a testing election in March, when he says Israel has "no partner" for peace. Mr Olmert will only weaken his new centrist Kadima party if he is seen making any concessions to what the Likud leader, Binyamin Netanyahu, yesterday ominously but predictably dubbed "Hamasistan".

Outsiders such as the EU and US should watch to see if conditional engagement will increase their leverage and encourage Hamas to take the gun and the bomb out of Palestinian politics. Victory for Hamas is a Middle Eastern earthquake that may bring new opportunities to the immense task of building peace between two peoples who have been fighting for far too long in the same small country. But for the moment it is the dangers that are far more obvious.

Mahmoud Zahhar is believed to be the leader of the Palestinian Islamic Resistance Group, Hamas, in Gaza.

A surgeon who teaches medicine at the Islamic University in Gaza, Mr Zahhar helped found the group in 1987 with Sheikh Ahmed Yassin.

He became a member of the "collective leadership" of the militant group in 2004 after Sheikh Yassin and Abdel-Aziz Rantissi were assassinated by Israel.

Mr Zahhar is one of Hamas' ideological leaders and is considered to be more hardline than Ismail Haniya, who headed the group's national list of candidates for the January legislative elections.

Medic

Mr Zahhar was born in 1945 in the Zeitoun neighbourhood of Gaza City to a Palestinian father and an Egyptian mother.

Having spent much of his youth in Egypt, he remained in the country to study medicine at Cairo's Ain Shams University.

After graduating in 1971, Mr Zahhar spent a further five years at Ain Shams specialising in general surgery.

He then returned to the occupied territories to lecture at the Department of Medicine of the newly created Islamic University of Gaza, where Rantissi also worked.

There, Mr Zahhar joined the local offshoot of Egypt's oldest and largest Islamist organisation, the Muslim Brotherhood.

Hamas founder

In 1987, a mass uprising - or intifada - against the Israeli occupation began in Gaza and quickly spread to the West Bank.

Palestinian Muslim Brotherhood leaders in Gaza became increasingly worried that they were losing support to more radical and militant Islamist groups, such as Islamic Jihad, and decided to form Hamas.

The group's covenant, published in August 1988, rejected any compromise with Israel and called for an Islamic state to be founded in its place. The Israeli authorities banned Hamas shortly afterwards.

Mr Zahhar and Rantissi, went on to lead the group after Sheikh Yassin was arrested by Israel in 1989 and sentenced to life imprisonment for ordering the killing of Palestinians who had allegedly collaborated with the Israeli army.

In December 1992, Mr Zahhar, his brother, Fadel, and Rantissi were among more than 400 Islamic activists deported by Israeli Prime Minister Yitzhak Rabin to South Lebanon.

The activists spent more than a year camped at Marj al-Zahour, where Hamas received unprecedented media exposure and became known throughout the world.

Though Mr Zahhar and Rantissi were allowed to return to Gaza a year later, 18 activists, including his brother, remained in Lebanon.

Back in Gaza, Mr Zahhar soon clashed with the Palestinian authorities. He was arrested several times by Palestinian security forces and at one stage spent seven months in a Palestinian jail.

Air strikes

With the outbreak of a new intifada in September 2000, Hamas's popularity among the Palestinian population grew rapidly as the organisation's military wing, the Izzedine al-Qassam Brigades, killed a large number of Israeli civilians in a new campaign of suicide bombings.

Israel responded by targeting Hamas' military and political leaders.

On 10 September 2003, only three days after a failed attempt to kill Sheikh Yassin, Israel bombed Mr Zahhar's home in Gaza, destroying it completely.

Mr Zahhar survived the attack, but his 25-year-old son, Khaled, and a bodyguard were killed.

Sheikh Yassin and Rantissi were not, however, so fortunate.

An Israeli air strike killed Hamas' spiritual leader on 22 March 2004, and Rantissi was assassinated just weeks after it was announced that he would take over as leader in the Gaza Strip.

Wary of further attacks, Hamas kept the appointment of Rantissi's successor secret.

However, Palestinian sources said the group's new leaders in Gaza were Mr Zahhar, Ismail Haniya and Sayyid al-Sayyam.

'Right to resist'

Since then, Mr Zahhar has been influential in getting Hamas involved in the Palestinian political process.

The group agreed to an informal truce with Israel which began in February 2005, and Hamas took part in elections for the first time.

Although the international community has called on Hamas to renounce violence, Mr Zahhar has insisted his organisation has the "right to resist" Israeli attacks.

"We are not playing at terrorism or violence. We are under occupation," he said.

"The Israelis are continuing their aggression against our people, killing, detention, demolition and in order to stop these processes, we run effective self defence by all means, including using guns."

While insisting on the right to "resist" he has also floated the possibility of holding peace talks with Israel via a third party.